Tatsuo Ishii <t-ishii@sra.co.jp> writes:
> Just for a testing I made a huge table (>2GB and it has 10000000
> tuples). copy 10000000 tuples took 23 minutes. This is not so
> bad. Vacuum analyze took 11 minutes, not too bad. After this I created
> an index on int4 column. It took 9 minutes. Next I deleted 5000000
> tuples to see how long delete took. I found it was 6
> minutes. Good. Then I ran into a problem. After that I did vacuum
> analyze, and seemed it took forever! (actually took 47 minutes). The
> biggest problem was postgres's process size. It was 478MB! This is not
> acceptable for me. Any idea?
Yeah, I've complained about that before --- it seems that vacuum takes
a really unreasonable amount of time to remove dead tuples from an index.
It's been like that at least since 6.3.2, probably longer.
regards, tom lane